Rendering of geographic information in 3-dimensions requires efficient techniques for determining what graphical elements contribute to the scene and should be included in the visualization. Moreover, this determination must be performed repeatedly during the process of animation when the graphical elements are dynamic and their characteristics and geometric relationships change between animation frames.
Of particular interest in such visualizations is the depiction of the region of obstruction from a particular viewing location created by an ellipsoidal object such as the Earth, Moon, or other celestial body. Visualization of this region of obstruction is of importance since it serves to indicate limitations on what can be observed from a particular vantage point.
Also of interest is the restriction of a defined view volume, such as the field of view of a sensor, due to the ellipsoidal obstruction, since it allows visualization of the limitations imposed on the volume by the obstructing body.